wallis mechanical normalization system for low back pain

Conditions: Low Back Pain

Summary: the purpose of this study is to compare improvement in low back pain with wallis (interspinous process implant) to exercise and injections.


Eligibility criteria:
subjects must meet all inclusion and exclusion criteria listed below for participation in the study. inclusion criteria: * ages 18-60; male/female. * diagnosis of mild to moderate degenerative disc disease (ddd), which requires: * back pain of at least 30/100 as measured on a visual analog scale, with or without leg (radicular) pain; and * radiographic confirmation of the following, as determined by computed tomography (ct), magnetic resonance imaging (mri), discography, plain film, myelography and/or flexion/extension films: up to modic i changes on mri, with decreased disc height up to 50% of adjacent level, and no significant osteophytes; with or without a contained disc herniation. * candidate for either surgery with wallis or aggressive conservative management. * requires treatment at one or two lumbar levels between l1 and l5. * experienced symptoms for at least three months without significant resolution. * has undergone a regimen of at least four weeks of anti-inflammatory medication for the current episode of back pain and had exposure to physical therapy. * minimum baseline oswestry score of 30% (15/50). * physically and mentally able to comply with the protocol, including ability to read and complete required forms, and willing and able to adhere to the follow-up requirements of the protocol. * voluntarily signs the subject informed consent. exclusion criteria: * significant neuroforaminal compression requiring discectomy or foraminotomy * radiographic evidence of ddd at l5-s1 * radiographic confirmation of severe facet joint disease or degeneration. * history of any lumbar disc treatment intended to remove the disc, e.g. surgery, intradiscal electrothermal therapy (idet), laser or enzymes such as chymopapain. * clinically compromised vertebral bodies at the affected level due to current or past trauma, e.g., sustained pathological fracture or multiple fractures of vertebrae. * unwilling to comply with 8 weeks of physical therapy. * subject refuses to consider epidural or facet injections for leg or back pain. * active systemic infection or infection at the operative site * osteoporosis. the simple calculated osteoporosis risk estimation (score) questionnaire will be used to screen subjects for osteoporosis; subjects whose screening suggests risk will undergo a dual-energy x-ray absorptiometry (dexa) scan. subjects will be excluded if the dexa scan results indicate a t-score equal to or worse than -2.5, in accordance with the world health organization definition of osteoporosis. * paget's disease, osteomalacia, or any other metabolic bone disease other than osteoporosis, which is addressed above * rheumatoid arthritis, lupus, or other autoimmune disease * aids, hiv, or hepatitis * known allergy to titanium, polyetheretherketone, or polyester * current pathological lesions, such as tumor * congenital lumbar spinal stenosis * clinically relevant instability on flexion-extension as determined by the investigator by overlaying films. * cauda equina syndrome * pregnant at time of enrollment or with plans to become pregnant within the next three years * concomitant conditions requiring steroid treatment or prior steroid usage for more than one of the preceding three months * diabetes mellitus requiring daily insulin management * extreme obesity, as defined by national institutes of health (nih) clinical guidelines (body mass index \[bmi\] \> 35) * fusion previously performed at the same or an adjacent level; or other instrumented spinal surgery at the operative level. * prior participation in study of any experimental spinal implant or treatment * pending litigation against a health care professional * life expectancy of less than three years * history of any invasive malignancy (except for non-melanoma skin cancer), unless treated with curative intent and with no clinical signs or symptoms of the malignancy for at least 5 years * current or recent history of substance abuse (alcoholism and/or narcotic addiction) requiring intervention * spondylolysis * translation greater than 2 mm at the symptomatic level * significant scoliosis (cobb angle \> 25 degrees) or scoliosis otherwise requiring surgical correction * kyphosis requiring surgical correction

Keywords: degenerative disc disease of the lumbar spine